Viewing page 21 of 195
This transcription has been completed. Contact us with corrections.
36 Monday May 8th 1843 Phosphorogenic emination transmissibility of different substances for Experimented on the relative transmissability of different susbstances for the phosphoregenic emination. The following appears to be the order as obtained by comparing one with another. [[underlined]]1st series of exp[[/underlined]] Rock crystal Calc spar Sulphate of Barita [[underlined]] 2nd series [[/underlined]] Rock crystal Calc spar very little difference Salt Alum [[underlined]] 3rd series [[/underlined]] Sul barita White glass Viol[[e]]t [[strikethrough]] Red [[/strikethrough]] glass Red glass Mica [[underlined]] 4th series [[/underlined]] White glass Mica Tourmaline [[underlined]] 5th series[[/underlined]] Rock crystal Sulphate of lime Calc spar [[underlined]] 6th series [[/underlined]] Fluor spar Calc spar Sulphate of Barita Transmitted the emination through quartz cut perpendicularly to the axis, and obliquely to the same, but could not perceive any difference in the intensity of the light. Tried the same experiment with calc spar, but no difference in the result was observed, although the difference in thickness of the two pieces of spar was. On sunday the 7th - There was a thunder shower which as usual came from the south west and passed at a great elevation above Princeton - several needles were magnetized in my study by the flash. with the same apparatus which failed a few days since to give any results when it was connected with the long wire. It was on the 7th connected with the roof of the house. [[end page]] [[start page]] Tuesday May 9th 1843 37 Mr Professor Hamilton informes that within the last three years he has observed 5 or 6 cases of houses struck with lighting, and in each of these the discharge was on the end of the gutter or in the vicinity of the same. He knows of but one exception to this, and then the whole house was surrounded by water as if the building were on an island. It was struck at the chimney. The house was in a hollow - does not know if the chimney had fire in it at the time. This fact in reference to the gutter [[overwritten]] are [[/overwritten]] is in accordance with the explanation I gave of the phenomena of the striking of old Mrs Hamiltons Houses (see back vol) May 9th. Commenced to day with the manipulation of the Daguerrotype process in order to study the chemical emination in connection with that of the Posphorogenic. [[image: a box with 6 small squares inside it that are numbered, placed in two rows of three; 3 squares in the first row, labeled 1,2,3 from left to right; 3 squares in the second row labeled 4,5,6.]] A prepared plate was placed under a block of wood, through which holes were cut as represented in the figure, and over these holes were paced plates of different transparent substances, [[underlined]]Viz[[/underlined]] over No 1 mica, No 2 glass, No 3 Calc spar, No 4 Salt, No 5 Quartz, No 6 alum. The plate was then exposed to the diffuse light of the sky for about 2 minutes and then removed to the mercury. While the process was going on, the iodized plate underneath could be distinctly seen, and it appeared to change colour under each but under the cal spar the heat appeared dif[[hole in page]]nt. The final result of the experiment was not satisfactory, the whole effect was overdone, the spots No 1 2 & 3 were more solarized than those marked 4 5 6 - Tried the same experiment, but the time was again too long to indicate any difference of result. The plate under each opening in the wood was marked as before. [[end page]]
